The present invention relates to a cushioning device, such as a mattress or mattress overlay, which self-adjusts to provide optimal support and interface pressure for a user.
Therapeutic supports for bedridden patients have been well known for many years. Such therapeutic supports include inflatable mattresses and cushions, as well as a variety of foam mattresses and cushions. Most therapeutic mattresses and cushions are designed to reduce xe2x80x9cinterface pressures,xe2x80x9d which are the pressures encountered between the mattress and the skin of a patient lying on the mattress. It is well known that interface pressures can significantly affect the well-being of immobile patients in that higher interface pressures can reduce local blood circulation, tending to cause bed sores and other complications. With inflatable mattresses, such interface pressures depend (in part) on the air pressure within the inflatable support cushions. Most inflatable therapeutic mattresses are designed to maintain a desired air volume within the inflated cushion or cushions to prevent bottoming. xe2x80x9cBottomingxe2x80x9d refers to any state where the upper surface of any given cushion is depressed to a point that it contacts the lower surface, thereby markedly increasing the interface pressure where the two surfaces contact each other.
One type of therapeutic support is an inflatable cushion used as an overlay (i.e., a supplemental pad positioned on top of an existing structure, such as a mattress). For example, the Sof-Care(copyright) cushions of Gaymar Industries, Inc. are cushions which overlay an existing mattress and which include a multitude of lower individual air chambers and a multitude of upper individual air chambers with air transfer channels therebetween. Air is transferred through the interconnecting channels to redistribute the patient""s weight over the entire bed cushion. A three layer overlay cushion known as the Sof-Care(copyright) II cushion continually redistributes patient weight through more than 300 air-filled chambers and may include hand grips at the side of the cushion to assist in patient positioning. In these types of cushions, the individual air chambers remain pressurized.
However, when the overlay cushions described above or inflatable mattress units are used, a separate pump or air source is typically required to adjust the pressure in the inflatable cells. Such adjustment is required for each user when initially using the cushion or mattress and to make any changes to the air pressure within the air cells during use.
Thus, these cushioning systems are multi-component systems including two major components, an inflatable portion and a pump/air source. Therefore, these cushioning systems are more expensive and are more difficult to use by untrained users. Moreover, these cushioning systems require user interface or manual adjustments to control pressure within the device.
Accordingly, there remains a need for a simple cushioning device which does not require a pump device/external fluid source to adjust the pressure within the cushioning device. The present invention is directed to overcoming these and other deficiencies in the art.
The present invention relates to a cushioning device including a first fluid bladder support structure having a first surface and an opposing second surface, a second fluid bladder support structure having a first surface and an opposing second surface, and at least one fluid accumulation reservoir. The first and second fluid bladder support structures deform under application of a load and reform upon removal of the load. A first conduit interconnects the first bladder support structure in fluid communication with the second fluid support structure. The first conduit includes a first one-way valve which permits fluid flow from the first fluid bladder support structure to the second fluid bladder support structure. A second conduit interconnects the second fluid bladder support structure in fluid communication with at least one fluid accumulation reservoir. The second conduit includes a second one-way valve which permits fluid flow from the second fluid bladder support structure to the at least one fluid accumulation reservoir and which is a pressure relief valve. A third conduit interconnects the at least one fluid accumulation reservoir in fluid communication with the first fluid bladder support structure. The third conduit includes a third one-way valve which permits fluid flow from the at least one fluid accumulation reservoir to the first fluid bladder support structure.
The present invention also relates to a cushioning device including at least one fluid bladder support structure having a first surface and an opposing second surface and a fluid accumulation reservoir structure, wherein the at least one fluid bladder support structure is positioned within the fluid accumulation reservoir structure. The at least one fluid bladder support structure deforms under application of a load and reforms upon removal of the load. At least one pressure relief valve is provided in fluid communication with the at least one fluid bladder support structure and the fluid accumulation reservoir structure. The at least one pressure relief valve is a first one-way valve which permits fluid flow from the at least one fluid bladder support structure to the fluid accumulation reservoir structure. At least one second one-way valve is provided in fluid communication with the at least one fluid bladder support structure and the fluid accumulation reservoir structure. The at least one second one-way valve permits fluid flow from the fluid accumulation reservoir structure to the at least one fluid bladder support structure.
Another aspect of the present invention relates to a cushioning device including at least one fluid bladder support structure, a plurality of fluid accumulation reservoirs, and at least one shut-off valve. The fluid bladder support structure deforms under application of a load and reforms upon removal of the load. The plurality of fluid accumulation reservoirs are interconnected to be in fluid communication. The manual shut-off valve is in fluid communication with the fluid bladder support structure and at least one of the plurality of fluid accumulation reservoirs. As used herein, a plurality comprises two or more fluid accumulation reservoirs.
Yet another aspect of the present invention relates to a cushioning device including at least one fluid bladder support structure and at least one fluid accumulation reservoir interconnected in fluid communication with the fluid bladder support structure. The fluid bladder support structure deforms under application of a load and reforms upon removal of the load. The fluid accumulation reservoir has a movable adjustment device which adjusts the volume of the at least one fluid accumulation reservoir.
The cushioning device of the present invention provides a simple, one-component device for home or hospital use for providing pressure relief so that pressure ulcers may be eliminated or retarded. The air cells in the support bladder of the cushioning device are in fluid communication with a reserve reservoir to continually self-regulate, balance, and conform to the therapeutic needs of the user. Thus, the cushioning device of the present invention provides self-adjusting, customized pressure management. Further, the cushioning device may include multiple, independently adjusting zones in the support bladder, without the need for multiple reserve reservoirs for such independent zones (thus increasing the support area available for the user of the cushioning device). Moreover, a resilient device, if present within the cells of the support bladder, applies no additional pressure to the fluid in the device. In addition, the cushioning device may be provided as a completely closed system, i.e., the device does not obtain fluid from an external source, such as atmosphere or a fluid pump. Thus, the cushioning device is not exposed to external contaminants and is protected from potential leaks (more common in systems pulling fluid from an outside source). In addition, the elimination of the need for an external pump device reduces costs and makes the cushioning device easy to use for an untrained user.